Solution of a quadratic equation
and reduced quadratic equation.
In general case of a non-reduced quadratic equation:
ax 2 + bx + c = 0 ,
its roots are found by the formula:
If to divide all terms of a non-reduced
quadratic equation by
a
(is it possible
?), and to sign
b / a = p
and
c / a = q ,
then we’ll receive the
reduced
quadratic equation:
x
2
+ px + q = 0 ,
roots of which are calculated by the
formula:
E x a m p l e . x 2 + 5 x + 6 = 0 . Here p = 5, q = 6. Then we have:
hence, x 1 = – 5 / 2 + 1 / 2 = – 2 , x 2 = – 5 / 2 – 1 / 2 = – 3